Construction of sheet-metal-pjpe sections



(No Model.)

J. B. ROOT.

CONSTRUCTION OF SHEET METAL PIPE SECTIONS. No. 283,924. I Patented Aug. 28; 1883.

mm, v E E FM W W EEEEE A UNITED STATES PATENT @rricn.

JOHN B. ROOT, OF PORT CHESTER, NEIV YORK.

CONSTRUCTION OF SHEET-METAL-PI'PE SECTIONS.

SPECIFICATION forming part of Letters Patent No. 283,924, dated August 28, 1883.

Application filed April 9, 1893. No model.)

T all 1071 0711 it may concern Be it known that 1, JOHN B. Roor, of Port more particularly the larger sizes, it has been larger ends thereof.

customary to only punch and shape the blanks of which the pipe-sections are composed at the factory. This is done with a view to economy in transportation, as the disconnected, pun ched, and shaped blanks can be packed within one another, so as to form nests made up of a number of blanks which occupy no more space than a single finished pipe-section would occupy. Such nests are shipped to the place where the pipe is to be used,when the longitudinal seams of the blanks are closed, and the pipe-sections thus completed are then riveted together end to end. Heretofore pipe of this kind has been made of cone-shaped sections, the larger end of a section being of a size to admit the smaller end of another section to a distance sufficient to make a proper joint. To produce this conical shape, the rivet-holes in the side edges of the flat blanks from which the sections are made must be along lines inclined to each other and to the edges of the sheets if they are rectangular, and in order that the holes in the connecting ends of separate sections shall correspond the distance between the holes in the smaller ends of the sections must be less than the distance between the holes in the To properly punch the holes in the fiat blank before it is shaped and preserve these variations requires no little care and precision, and is to a great extent necessarily done by hand, the workman being assisted by apattern or other guide constructed to indicate the correct position of the holes; but the accuracy of hand-work is not con stant or reliable, and errors are continually occurring which result in poorly-fitting work.

It is therefore the object of my present invention to produce pipe-blanks analogous to those just described entirely by automatic means and of an improved shape.

In the accompanying drawings, Figure 1 represents a plain punched and partially shaped pipe-blank. Fig. 2 represents oifsetting rolls operating upon one end of such blank. Fig. 3 shows the finished blank, and Fig. 4 illustrates two sections of the piperiveted together. I

In carrying out my invention, the first step consists in submitting the flat rectangular Sheet-metal blanks from which the pipe is made to the action of a properly-adjusted gang of punches driven by some appropriate power, and thereby forming along and parallel with the edges and ends of the blanks lines of rivetholes A, such holes being all the same distance apart, and then bending the flat blank into an open cylinder, B. v

Thesecond step consists in passing one of the ends of the cylindrical blanks between. rolls 0, to expand the stock and form offsets D of a sufficient depth to, in the completed that is, longitudinally-closedsections, receive the smaller or unexpanded ends of the sections,

and of suitable width to make a tight and strong joint, and in thus enlarging the ends of these blanks the stretching which the metal undergoes separates the rivet-holes proportionately to the increase in the diameter of the blanks, and, accordingly, to the right distance for the holes in the larger ends of the completed sec tions to coincide with the holes in the smaller end of the sections when such larger and smaller ends are brought together in forming the pipe.

Since the Various operations are performed entirely by mechanical means, the completed sections of pipe are practically exact duplicates of one another, and can therefore be joined up into any continuous length without regard to special arrangement or further triniining or fitting. The cylindrical shape of the sections facilitates the forming of stronger and closer joints, and gives to the finished pipe not only amorc substantial character in other manifest respects, but offers less resistance to the material flowing through the pipe than is the case with pipe made up of conical sections.

It is plain that other devices than rolls may be used for offsetting the ends of the blanks, and hence I do not confine myself to rolls for this purpose.

Although I have described and shown blanks designed to be closed at a straight longitudi nal seam, Ido not limit myself to such eonstruetion, as the blanks can be closed along a spiral seam, and sections made with such seams are for some purposes preferable and cheaper.

What I claim as new is 1. Asa new article of manufacture, a cylindrically-formed sheet-nietal-pipe blank one end of which is provided with an offset and both ends with rivet-holes, substantially as shown, and for the purposes set forth.

2. As a new article of manufacture, a cylindrical sheetmetal-pipe section provided with an offset at one end to receive the smaller end of a connecting section, and with rivet-holes at both ends, arranged substantially as andi 5 cylindrical form, and then forming an offset 20 at one end, substantially as described.

JOHN B; ROOT.

\Vitnesses:

ROBT. F. GAYLORD, R0131. H. DUNCAN. 

